Improvement in raising and lowering propeller-shafts



. M. B. ATKINSON 8a TE-JOHNSON. v RAISING AND LOWERING PROPELLEQB. SHAF'IS. No.1'7ZQ945. I Patented Feb.1, 1876.

WITNESSES mvENToRfi Wa fipM MPHEILQ FHOTO-LITHOGRAPHEFL WASHINGTON. D. C.

UNITED STATES PATENT OEEIcE.

' MAHLON B. ATKINSON AND THOMAS JOHNSON, OF GEORGETOWN, 1). 0.,

ASSIGNORS TO HENRY WAGNER, OF SAME PLACE.

IMPROVEMENT m RAISING AND LOWERING PROPELLER-SHAFTS.

Specification forming part of Letters Patent No. 172,945, dated February 1, 1876; application filed January 15, 1876.

To all whom it may concern:

Be it known that we, MAHLON B. ATKIN- soN and THOMAS JOHNSON, of Georgetown, in the county of Washington and District of Columbia, have invented a new and valuable Improvement in Steam-Propellers; and we do hereby declare that the following is a full,

, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, and to the letters and figures of reference marked thereon.

Figure 1 of' the drawings is a representation of a longitudinal vertical section of our will be hereinafter explained.

In the annexed drawings we have represented in detail the stern portion of a canalboat having our invention applied-t0 it.

A designates the shaft of a propeller, B, which latter may be constructed in-any suitable manner. The shaftA passes freely through a vertically-slotted stern -post,.0, through a water-tight housing, D, through a cylinder, E, and is journaled in the base of an engineframe, F. The cylinder E is jonrnaled in standards a, and is suitably packed against the housing D, so as to prevent the ingress of water, but allow the propeller-shaft to be vibrated vertically. The shaft A, where it passes through the oscillating cylinder E, is also packed water-tight. The frame F maybe constructed in any suitable manner, and at the upper portion of this frame is an enginecylinder, b, the piston-rod of which communicates rotary motion to the propeller-shaft. The engine-frame is rigidly connected by beams c c to the journals of the oscillating cylinder E, so that this frame, the shaft A,

and the cylinder E all move up'and down together.

Prior to our invention the movable parts above described were adjusted by means of a I screw. We now adjust them by the following means:

G designates a cylinder, which is pivoted to the standards a at i, and which has a piston in it, the rod 0? of which is pivoted to toggle-levers g g. The upper one of these levers is connected to the base of the engine-frame F, and the lower one is connected to the bottom of the boat, at c. On one side of the cylinder G is a chest, h, in which is a D-valve, the stern f of which is'attached to a lever, J, extending above deck.

The cylinder G, its chest, its valve, and ports are constructed precisely like an ordinary high-pressure engine.

This engine communicates with the waterspace of the steam-boiler usedfor driving the propeller, and,.when it is desired to raise or depress this propeller, it-is only necessary to movelever J in the proper direction,-and admit water from the steam-boiler on one side or the other of the piston in the cylinder G.

Instead of mounting cylinder G as shown in the drawings it may be placed directly beneath the frame F, and its piston-rod pivoted thereto. 1

It will be seen from the above description that we adjustthe propeller-shaft by a hydrostatic engine, taking the water from the boiler which drives the engine that operates-the propeller-shaft.

By using water under pressure in the cylinder G we have practically an incompressible body, and can hold the propeller-shaft positively wherever desired.

It is proper to state here. that the steam-englue and the hydrostatic engine will communicate with the steam-boiler by means of flexible pipes.

What we claim as new, and desire to secure by Letters Patent, is'

In combination 'with the vertically-adjustable propeller-shaft and its engine-frame, a

hydrostatic engine, applied substantially as described, for adjusting said shaft, as set forth. In testimou y that we claim the above we have hereunto subscribed our names in the presence of two witnesses.

' M. B. ATKINSON.

THOMAS JOHNSON. Witnesses:

EUGENE W. J oHNs'oN, JosB. Looms. 

